Duracell Specialty Alkaline MN27 Battery (A27)

Duracell MN27 (A27) Specialty Alkaline 12V Battery

The Duracell MN27—also labeled A27 or 27A—is a compact 12V alkaline cell engineered for miniature RF transmitters where space is tight but a strong pulse is needed. Common in certain automotive remotes, garage/gate openers, wireless doorbells, and small security devices.

When to Choose It

• Use if your device explicitly lists A27, MN27, or 27A.
• Best for short, infrequent pulses (e.g., key fob button presses) rather than continuous draw.
• Keep as a spare if your access system is critical; alkaline cells store well when kept cool and dry.

Avoid If

• Your device specifies A23/MN21 (larger diameter) or a coin cell like CR2032—these are not interchangeable.
• You need rechargeability—MN27 is a primary (single-use) alkaline cell.

Typical Uses

• Automotive key fobs and alarm remotes that call for A27
• Garage and gate transmitters
• Wireless doorbells and small RF gadgets
• Select sensors and compact security devices

Specs at a Glance

Runtime Expectations

Actual life depends on usage frequency, transmitter power, and temperature. As a general guide:

• Key fobs: often 6–24 months with typical daily use
• Doorbells/remote transmitters: several months to a year with moderate use

MN27 vs. MN21 (A23)

• Size: A27 is slimmer (≈8 mm Ø) than A23 (≈10.3 mm Ø); lengths are similar. They do not fit the same devices.
• Capacity: A23 typically offers higher capacity, but only use what your device specifies.

Installation

1. Confirm the code on your old battery or device label: A27/MN27/27A.
2. Insert with correct polarity: match the “+” end to the device’s positive symbol.
3. Wipe contacts with a dry, lint‑free cloth before closing the compartment.
4. Fully latch the cover; many remotes reduce range if the door isn’t seated.
5. Test at normal distance; re-seat the cell if response is weak.

Care and Safety

• Store in original packaging at 60–77°F (16–25°C), away from heat and humidity.
• Do not carry loose cells with keys or coins (short‑circuit risk).
• Remove the battery for long-term device storage.
• Keep out of reach of children and pets; ingestion and choking hazard.
• Recycle or dispose per local guidelines; do not recharge, crush, or incinerate.

Troubleshooting

• Intermittent operation: Clean contacts; verify you’re using A27 (not A23).
• No response after replacement: Check polarity and ensure the compartment is fully closed.
• Short life: Frequent button presses, extreme cold/heat, or a sticking button can drain the cell quickly.

FAQ

Is MN27 rechargeable?

No. It is a single‑use alkaline battery. Do not attempt to recharge.

Can I substitute A23 (MN21) for A27?

No. Although both are 12 V, they differ in diameter and capacity and are not interchangeable.

How long will an MN27 last in a key fob?

Typically 6–24 months, depending on how often you press the buttons, transmitter power, and temperature.

Does MN27 replace coin cells like CR2032?

No. MN27 is a slim cylindrical 12V battery; coin cells are flat 3V lithium cells and require different devices.